While questioning Blankenship and Main, Sen. Robert C. Byrd criticized both Massey and MSHA, telling a Senate Appropriations subcommittee hearing there is enough blame to go around following the worst U.S. coal-mining disaster in 40 years.

Byrd said Congress has given MSHA plenty of authority and money, but that such resources are "useless if the enforcement agency is not vigorous about demanding safety in the mines."

In a rare public appearance, the 92-year-old West Virginia Democrat also blasted Massey and scoffed at Blankenship's repeated insistence that Massey puts safety first in its mines.

"I cannot fathom how an American business could practice such disgraceful health and safety policies while simultaneously boasting about its commitment to the safety of its workers," Byrd said.

The hearing, held by a Senate panel that oversees MSHA's budget, provided a dramatic face-to-face confrontation between Blankenship and his company's harshest longtime critic, United Mine Workers President Cecil Roberts.

While the hearing was titled "Investing in Mine Safety: Preventing Another Disaster," the focus was clearly on Upper Big Branch and its aftermath.

Following a panel of government witnesses, including Main and other regulators, Roberts and Blankenship delivered short statements and took questions from lawmakers. Massey has been a mostly nonunion company since the mid-1980s and has systematically bought up formerly union coal operations -- including Upper Big Branch -- across Southern West Virginia.

Blankenship said his Richmond, Va.-based company has long been an industry safety leader, and flat-out dismissed any suggestions that he or Massey cut corners to increase production.

"Massey does not place profits over safety," Blankenship said. "We never have and we never will. Period."

But Roberts said that, even before Upper Big Branch, 23 miners had died at Massey operations in the last decade, a higher number, Roberts said, than any recorded by other major coal producers.

Blankenship said Massey's numbers are "probably about average," but that "any fatality is unacceptable to us."

Roberts responded, "This isn't average. This is deplorable is what it is."

Questioning Blankenship, Byrd lamented the deaths at Upper Big Branch saying, "Twenty-nine men are now dead. Dead. Dead, simply because they went to work that morning." And Byrd rattled off a long list of statistics about Massey's troubled safety record.

"This is as clean as the noonday sun," Byrd said. "This is a clear record of blatant disregard for the welfare and safety of Massey miners. Shame."

Subcommittee Chairman Tom Harkin, D-Iowa, quizzed Blankenship about the now-infamous October 2005 memo in which the Massey executive advised his staff to be sure to "run coal" before undertaking construction or safety projects at the company's mines.

"That doesn't sound like putting safety first to me," Harkin said, reading from the memo.

Blankenship said that the memo was "poorly drafted" and later corrected, "To make sure no one misunderstood it."

Harkin also pressed Blankenship about the plea agreement in which Massey subsidiary Aracoma Coal Co. admitted to 10 criminal violations in the deaths of two miners in a January 2006 fire. Blankenship responded by noting that the plea deal did not implicate the parent company or any of its officers in any wrongdoing.

"We do everything we can to get every one of our 7,000 employees to put safety first," Blankenship said. "I did everything I could do in advance of that fire."

Blankenship also repeated his company's previous allegations that prior to the April 5 explosion, MSHA had forced ventilation changes at Upper Big Branch that reduced the amount of fresh air getting to the mine's working face.

"We opposed the changes because our own engineers believed they made the mine less safe, not because they were more costly or because they interfered with production," Blankenship said.

Blankenship added, "We do not know whether the ventilation system played a role in the explosion, and we do not know whether the modifications to that system demanded by MSHA played a role in the explosion."

But Byrd said the implication was clear. "This sounds like someone is trying to blame your agency for the deaths of 29 miners," Byrd told Main.

Main said MSHA had ordered changes in the mine's ventilation system because agency inspectors had on several occasions found the flow of fresh air headed in the wrong direction, a major violation Main said put miners' lives at grave risk.

But, Main also came under criticism from Byrd, who demanded to know why MSHA did not take tougher action at Upper Big Branch prior to the explosion and only launched an "inspection blitz" on mines with repeated violations after the disaster.

"In retrospect, there should have been more enforcement tools used at that mine," Main said, when pressed by Byrd about Upper Big Branch's continuing safety problems. "We have shortcomings.

"The only thing I can say is that the agency didn't do it," Main said. "That's something we'll look at and try to figure out what we did or didn't do."